Sub-cm Resolution Distributed Fiber Optic Hydrogen Sensing with Nano-Engineered TiO2

TL;DR

This paper presents a high-temperature, sub-centimeter resolution distributed fiber optic hydrogen sensor using nano-engineered TiO2 with palladium nanoparticles, capable of detecting chemical gradients at temperatures exceeding 500°C.

Contribution

The study introduces a novel nano-structured TiO2-based fiber optic sensor with distributed sensing capabilities for hydrogen at high temperatures, demonstrating sub-cm resolution.

Findings

Detects hydrogen concentrations up to 10%

Operates reliably at temperatures above 500°C

Achieves sub-centimeter spatial resolution

Abstract

The 3D nano-structuring on the <10nm scale allows the refractive index of functional sensory materials(n>2) to be reduced and matched with the cladding of optical fiber(n~1.46) for low-loss integration. A high temperature capable hydrogen sensor composed of D-shaped optical fiber with palladium nanoparticles infused nanoporous (~5nm) TiO2 film is demonstrated. The behavior of the developed sensor was characterized by examining the wavelength of an incorporated Fiber Bragg Grating and by observing the transmission losses at temperatures up to 700C. In addition, with frequency domain reflectometry the distributed sensing potential of the developed sensor for hydrogen concentrations of up to 10% is examined. The results show the possibility of detecting chemical gradients with sub-cm resolution at very high temperatures(>500C).